Merge pull request #23 from AndyYou/master

fixed issue of progress
Merge pull request #24 from AndyYou/master

add sqlbulk copy progress
Merge pull request #25 from AndyYou/master

Modify key issue
Merge pull request #26 from AndyYou/master

fixed issue of backup when database exists
Create all tables when database not exist
Always delete last record
Merge pull request #11 from CalvertYang/master

Create all tables when database not exist